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Figaro is a ruby on rails gem. It uses a YAML file for all your configuration values. It prevents this file from being uploaded to the remote repository. Figaro has a friendly interface with Heroku. With a simple command, you can port all your production configuration data to Heroku. The default is the development environment. With the command above, Figaro gets all your configurations data to production. The command below gives the configuration data, stripe_api_key, for the 'application.yml' above.